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Hello, is the check engine light on?
Do you smell any foul smell from the exhaust when it runs rough?
How long does it run rough after you start it?
Is your coolant level getting low?
No problem, one more question. Does the issue occur if it sits for 2-4 hours or longer period of time?
When was the last time tune up was done?
Was this issue present before tune up was done?
The symptoms you are experiencing points towards a contamination in the cylinder when the vehicle sits for a while. Most common causes for that on this vehicle is a leaking fuel pressure regulator, leaking fuel injector or internally leaking intake manifold gaskets.
It is located on the fuel return pipe.
You will need a a fuel pressure guage. When you turn on the ignition it will show you the fuel pressure, see if the fuel pressure drops fast when ignition is turned off. Also check if there is gasoline present in the fuel pressure regulator vacuum hose. That indicates a leaking fuel pressure regulator.
I will opt ot and let another expert assist you.